Can downgrade the firmware to v2.1.?

I am using TIA 14 SP1. Just started a new project with S7 1500F-2PN. V2.50

Since TIA 14 is not compatible with Firmware v2.5 Can I downgrade the firmware to v2.1.

I am duplicating a previous project which had the same CPU but v2.1. firmware.

Is there any danger in downgrading this firmware?

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Split from CPU 1515F firmware.

Hello,

Perhaps the following topic might help:

New Firmware Version V2.5 for SIMATIC S7-1500 and ET 200 CPUs

Compatibility between CPU firmware and display firmware:
A SIMATIC S7-1500 CPU with a firmware version V2.5 can be operated with a display with a firmware version ≤ V2.5.

Replacement case:
When a CPU with Firmware Version ≤V2.1 are replaced with a CPU with Firmware V2.5, the STEP 7 project does not  have to be changed. Upgrade of the STEP 7 software is also not required.

Configuration of a CPU with Firmware V2.5 in TIA Portal Versions < V15:
CPUs with Firmware Version V2.5 can also be used with TIA Portal Versions < V15. The procedure for configuration with TIA Portal Versions in which the current firmware cannot be selected can be found in the following Entry:109744163

New properties of the CPUs with Firmware 2.5:
To use the new functionalities, configuration in the TIA Portal STEP 7 Professional V15 or higher is required. (109752225)