When I used v1.3.3, the wallet is blocked by Chinese Great Wall firewall.
@jbg said he can help solve the sync problem in new wallet.
However, I can't sync yet with the new v1.3.5 and v1.3.6.
I asked in the discord but have no response.
Thanks for reporting, I wasn't able to sync while using obfs4 either. We'll look into it, please don't give up raising this problem until it is solved!
There are a lot of messages in Discord, just ask from time to time ... or create a Github ticket if you like. https://github.com/XSPECOfficial/spectre