After renewed my EasySocial subscription

Hi

I have got a very basic question, bear with me...

What is the difference in terms of the process between when I simply renew my easysocial subscription after it was expired (no version upgrade) and when I want to upgrade the version to the latest during my subscription period?

It look like I have to download launcher and install via Joomla's Extension Manager for both occasions.
Is it correct? Am I misunderstanding the process?

The reasons that I asked is that I have few customisation added to some easysocial core files and I recently renewed my subscription.. I want to know what is the next step..
If I still have to install launcher via Joomla's Extension Manager, I would imagine that all my customisation will be overridden..?

Thanks