Rotating Logfiles

How does loki/promtail handle rotating log files?
Could it be possible that the log file gets somehow blocked by promtail?

I currently have a python application which is writing ~ 5GB of logs every day which i am compressing from at regular intervals to save disk space.
Firstly, the file is renamed and then it gets compressed.
Is it possible that promtail will block this process while processing/reading it?

Please moderate your language on this public forum.

Antony.