In my experience, in China as of 2016, "ssh -D" vasn't reliable at all, I wrote more details at https://blog.zorinaq.com/my-experience-with-the-great-firewa... (see "idea 1")

I just spent 3 months in China this summer. The GFW has become much more sophisticated than I remember. I found only one method that reliably worked. That was to use Holafly (an international eSIM provider) and use its built-in VPN. China largely doesn’t care if foreigners get around the GFW, I guess.

Another method that usually worked was ProtonVPN with protocol set to Wireguard. Not sure why this worked, it’s definitely a lot more detectable than other methods I tried. But as long as I rotated which US server I used every few days, this worked fine.

No luck with shadowsocks, ProtonVPN “stealth” mode, Outline+Digital Ocean, or even Jump / Remote Desktop. Jump worked the longest at several hours before it became unbearably slow, I’m still not sure if I was actually throttled or my home computer started misbehaving.

I didn’t get around to setting up a pure TLS proxy, or proxying traffic through a domain that serves “legitimate” traffic, so no idea if that still works.

Regarding your usage:

Organic Maps app can download all maps for offile and works OK in China.

It uses openstreetmap data.

1024 bit RSA keys is laughable. I'm inclined to think this was not by accident.

Idea 1 and 2 are basically the same.