If you're desperate, try unchecking "Include bitcode for iOS content" and "Upload your app's symbols." This just worked for me after I found the workaround on twitter. Maybe this way I can at least get the iOS14 fixes out before the weekend.

I wouldn’t assume anything here. Rather, use maximumDatagramSize to see if your packet will fit. I'm a little confused about the number being returned here. As I send each frame, the majority are going through despite being significantly larger than this number. Here's a log where I log the data count I'm sending vs maximumDatagramSize. Only when there's a spike does the frame freeze and I see that error message. Sending size: 15344 - maximumDatagramSize reported: 1472 Sending size: 18182 - maximumDatagramSize reported: 1472 Sending size: 17145 - maximumDatagramSize reported: 1472 Sending size: 14539 - maximumDatagramSize reported: 1472 Sending size: 16288 - maximumDatagramSize reported: 1472 Sending size: 19660 - maximumDatagramSize reported: 1472 Sending size: 25691 - maximumDatagramSize reported: 1472 Sending size: 52437 - maximumDatagramSize reported: 1472 2021-05-24 08:49:08.983732-0400 App Name [23702:7182702] [] nw_protocol_ipv4_frame_output_finalizer [C3:2] Not enough bytes to fragment 52445 I'm unable to find any information on that particular error message and although I see it in the console, there is no NWError in the completion block of connection.send.