Hi @ivandeex, and sorry for the delay in getting back to you -- lots of stuff happening in 'RL', only today I was able to get back to this.
I too have experienced Jottacloud token expiration, in the context of having the same remotes configured in more than one machine simultaneously. The symptom being that trying to access the JC remotes in a machine where they weren't used recently, results in errors like:
[REDACTED] couldn't get customer info: Get "https://api.jottacloud.com/account/v1/customer": couldn't fetch token - maybe it has expired? - refresh with "rclone config reconnect [REDACTED]:": oauth2: cannot fetch token: 400 Bad Request
Response: {"error":"invalid_grant","error_description":"Stale token"}
What I've been doing to re-establish access is to copy the relevant parts of ~/.rclone.conf from the machine which last accessed it (and where it is working), to the ones which were getting the above error. Right now I do it by manually grepping the config file in that machine for the appropriate lines, and sending the result to a location where it can be downloaded by the other machines and then incorporated into their config file in place of the ones with the expired tokens.
In this context, your --config-to addition is appreciated but not really practical, the reason being that the "machine who most recently accessed JC" has a public address on the internet (it runs on a server of mine), but the others don't (being behind NAT, etc). something that would work much better would be the other way around, eg a --config-from option where these "other" rclones would then contact the "server" rclone and 'pull' the configuration, instead of having it 'pushed' to them.
Thanks for your efforts and reporting, much appreciated!
Cheers,
--Durval.