Trouble with dynamic shadows and planar reflectoin. Looking for a bit of help.

Hey all looking for a little help understanding dynamic shadows within a planar reflection. I’ve copied the mirror out of the free swimming pool asset from the unreal market place into a project I’m playing with. Whenever I’m in front of the mirror (gameplay or viewport editor) my performance plummets. GPU widget shows this planar reflection is at 240ms. Anyway, if I untick “dynamic shadows” in the planar settings it goes away. Strangely, however if I utilize the same mirror within the original swimming pool project with dynamic shadows enabled, there is no issue. Any thoughts on what could be the cause? Tried to do a bunch of reading, but haven’t found a clear answer. If someone could point me in the right direction I’d really appreciate it.

AMD Ryzen 9 3900x 12 core 3.79GHz
NVIDIA GeForce GTX 1660 Ti

of course… as soon as I post this, I figured it out. Looks like I had some old lights on the map when I was originally building the scene that had really large attenuation radius’ that were making the system perform extra calcs and work in over-drive.