catchup feature failing to fetch reasonable number of posts

### Site

main site, dev site or localhost

### Version

_No response_

### Instance

fosstodon.org

### Browser

firefox 148.0.2 on opensuse tumbleweed also seen in chromium 146

### Bug description

recently I started seeing an issue where phanpy would fetch less than expected, say overnight would be expected 750ish posts
sometimes after trying again after a few minutes i might be able to fetch a larger amount
but now I am seeing sub 200 on a good fetch, and 25-50 when local hosting
bad is zero posts, and is happening more often.

not noticed any issues rapid scrolling (holding end key) feed on normal site or elk instance

### To reproduce

use catchup feature and pull anything

### Expected behavior

see above

### Other

_No response_