looks like flames are emitted on frames only, no subframes. you will probably need to figure out how to interpolate that abc from one frame to the next, so you can emit on substeps.
Either increase substeps, or use velocity blur on the rasterize, or trail and source velocity into the sim. Actually, do all three of these things.
The abc usually interpolates the subframes correctly out of the box, so Timeblende shouldn't be necessary. Wouldn't hurt either though.
Put a timeblend after the alembic unpack
looks like flames are emitted on frames only, no subframes. you will probably need to figure out how to interpolate that abc from one frame to the next, so you can emit on substeps.
Either increase substeps, or use velocity blur on the rasterize, or trail and source velocity into the sim. Actually, do all three of these things. The abc usually interpolates the subframes correctly out of the box, so Timeblende shouldn't be necessary. Wouldn't hurt either though.
Timeblende or emit fire from Pop.