Upgrade during a free trial period on same group

We have a service offering a 1-month auto-renewal subscription with a free-trial period.

We have 3 products, all on the same subscription-group, renewing every month, all offering 1-month free-trial.

What happens if the user subscribe to the level-1, get its free-trial then upgrade to the level-2 during this free-trial period ?

Will it loose its free-trial period ? or will it be migrated to the level-2 until the end of the free-trial ?

Thanks :)

We have a similar situation. Any information about this?

Upgrade during a free trial period on same group
 
 
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