'Catch up by' date calculation should start from last interaction, not the time I set the frequency

I am new to Dex so I am setting catch up frequency (1 month, 3 month and etc) on many contacts now. The catch up by date and alert are automatically set to 1 month or 3 month from now, which is not what I want. I would love it to be set based on last interaction. For example, if I have not talked to a contact on '3-month-frequency' since April, then the next catch-up alert should be in July. If I talk to a contact of the same update frequency last week, then the next catch-up alert should be in August.