Hi @Imtherealeddie ,
As per my email reply.
It isn’t a bug related to 1.10 or 1.10.1
The reason you encounter this issue is that your cache plugin cached the nonce for more than 12 hours. Using expired nonce will cause this 403 error.
You should lower the TTL of your cache plugin to 8 hours maybe.
Please refer to this forum thread SOLVED: Nonce problem with “Load more button” - #2 by itchycode
Regards,
Jenn