Add Different Start dates inside an Epic for BE anda FE work, to support a better capacity planning projection

I am trying to do capacity planning but there is no separation between Frond end and Back end start date (and it is affecting capacity planning)

We plan our roadmap at the epic level.

What we’d need is the tool to consider two separate dates for the epic start date: FE and BE.

We have created the FE team and BE team already, but if we set a start date, that is automatically taken into account for all work. For 90% of our epics BE starts about 1 month or 2 sooner than the FE.

I cannot do capacity planning at the moment because it is not accurate. It shows me an overload for October for FE but that is not true and no FE work will start now, only BE starts.