We’ve upgraded how ads and filler content are configured on Dynamic Blocks to give you more flexibility and control over playback. This guide explains what’s changed and how to move from the legacy toggle-based setup to the new Fill Sequence model.
| ℹ️ If you weren’t using ads on Dynamic Blocks: Most customers fall into this category. There is nothing to migrate — the new Fill Sequence system is entirely new functionality you can start using right away. Skip ahead to Fill Sequences below to learn what’s now available to you. |
What’s Changed
Previously, ads on Dynamic Blocks were configured using a simple toggle-based setup. The new system introduces Fill Sequences (shown as Custom Sequence in the UI), allowing you to define exactly what plays before, during, and after your content. You can now configure three segments:
- Pre-roll — before content starts
- Breaks — between videos in a block
- Post-roll — after all main content videos finish
Each segment supports a fully customizable sequence of assets.
Fill Sequences (Custom Sequence)
A fill sequence is an ordered list of items that can include Ads, Bumpers, and Videos. Each item pulls from a specific content pool (collection) and has a maximum number of assets to insert. You can define as many steps as needed, in any order.
| Example (Pre-roll sequence): • 2 Ads → Collection A • 1 Bumper → Collection B • 1 Ad → Collection B |
Duration-Based Filling
Fill sequences are applied only as long as they fit within the Dynamic Block’s total duration. For example, if a block is 60 minutes long and main content takes 50 minutes, the system will insert assets from your sequence into the remaining 10 minutes of available filler time without exceeding the block duration.
Best-Effort Insertion (vs. Legacy Behavior)
This is a key behavioral change from the legacy system:
- Before: You enabled pre/post-rolls via toggles, and the system inserted as many ads as would fit.
- Now (Custom Sequence): You define a maximum number of items per step, and the system makes a best effort to follow that sequence within the available time.
This means not all configured items are guaranteed to play — playback depends on timing and asset durations.
Breaks vs. Mid-rolls
These are now clearly separated concepts:
Breaks (Between Videos)
- Configured via Fill Sequences
- Applied only when a Dynamic Block contains multiple main content videos
- Represent filler content between videos (e.g., bumper → ad → bumper)
Mid-rolls (Within a Video) — Unchanged from the legacy system
- Occur inside individual videos, not between them
- Triggered by existing ad markers/timings in the video, or a fixed interval (e.g., every 5 minutes)
Post-roll Configuration
Post-roll sequences work the same as pre-roll, but are applied after all main content videos have finished, as long as there is remaining time in the block.
Fill Methods
Fill sequences support two playback strategies:
Custom Sequence (Priority Order)
- Assets are inserted in the exact order defined
- Each step respects its max item count
- Steps may be skipped if assets are unavailable or time runs out
Random
- Assets are selected randomly from the associated collection
- No strict ordering between asset types
- Useful for variety and rotation
Frequency Capping
You can define frequency caps per asset type within segments to avoid repetition. For example, “Do not reuse ads that aired in the last 2 hours.” This helps reduce repetition and improve content rotation. Frequency caps apply independently per asset type and segment.
Previews
Two types of previews are available to help visualize your configuration:
Structure Preview (Edit Mode)
- Visible while editing your sequence
- Displays the order of segments (pre, content, break, and post)
- Shows the sequence layout without real assets
Playback Preview (After Saving)
- Available on the Preview tab after saving
- Shows real content (videos, ads, bumpers) with actual durations
- Reflects how the block will actually play back
Fallback Behavior
If there is remaining unfilled time after applying your sequences, the system will use the channel’s fallback slate to fill the gap. A warning is displayed in the preview when this occurs. This ensures the block always matches its intended duration.
Key Benefits
- Fine-grained control over playback structure
- Mix ads, bumpers, and videos in a single sequence
- Reusable content pools
- Deterministic or randomized playback
- Reduced repetition with frequency capping
- Visual previews for validation
Migration Tips
If you were previously using the legacy ad toggle setup, follow these steps to recreate your configuration using the new Fill Sequence model:
- Map your existing setup into Pre-roll, Break, and Post-roll segments.
- Organize assets into content pools (collections).
- Recreate your flow using Custom Sequence (priority order).
- Validate against block duration constraints.
- Use Previews to confirm behavior before publishing.
- Add Frequency Caps to improve rotation.
| ℹ️ Tip: If you were using a simple ad-only setup before, you can replicate it with ad-only sequences and gradually introduce bumpers, videos, and more advanced configurations. |
Related Articles
- What’s New in Dynamic Block Builder
- How to Create a Block with Dynamic Block Builder
- Frequency Capping and No-Repeat Windows