I have a HooToo TM06 and have used OpenWRT (GL MT300 build) since 15 chaos calmer. It seems that with 18.06.1, large/fast file downloads stop shortly after starting (i can't even complete a speed test) and cause all other internet communication to cease until I restart either the WWAN or LAN interface from LUCI. This problem seems new to me. Nothing obvious in logs either (from LUCI). I am using wifi>wifi routing.
Regular internet browsing works fine until I need to download a large file.
Edit - I've just noticed this behavior also happens when using wired (WAN)>wifi routing, though it takes a bit longer to happen. I imagine i downloaded ~500mb before it happened this time. I also didn't have to restart any interface, I just resumed the download.
Any troubleshooting suggestions? Is this a known issue?