How can one avoid re-syncing the whole testnet chain after stopping and restarting "lotus daemon"

Hello Lotus developers,

When “lotus daemon” is stopped (e.g. Ctrl-C) and then restarted again (even within a short time), “lotus sync wait” cannot re-sync at all.

The only way to fix it is to delete the whole $LOTUS_PATH/datastore directory when the ‘lotus daemon’ is stopped, and then start up the daemon. After the daemon is started, you can then run “lotus sync wait”, which sync from the very beginning, which will take X days to complete (if it succeeds in the sync-process without getting stuck for no reason as reported by other people).

Is there a way for ‘lotus sync wait’ to sync-up the chain from where daemon was stopped without having to re-sync from scratch?

Update: It appears that if ‘lotus daemon’ isn’t stopped for too long, chain sync can resume successfully and syncs up quicky ('lotus sync wai’t completes successfully with the “Done!” message).

Meet the same issue, however I run lotus in docker container.
I write an issue also in github.