PP version 12.1.2
AE version 15.1.2
Right after import EXR sequence I "replace the clip with AE composition", both composition settings PP and AE to 25fps (default) but in AE the layer imported is shorter (the composition length is ok) than the original in PP. The video in PP lasts 07:04 while the layer in AE lasts 05:24 (both base 25).
Bug or nonsense functioning?.
In After Effects, go to Edit > Preferences > Import and make sure that Sequence Footage is set to 25. In Premiere Pro, go to Edit > Preferences > Media and set the Indeterminate Media Timebase is set to 25 as well.
None of those changes will change anything in what you have already done so you must redo the import of the EXR sequence and "replace the clip with AE composition" to see any changes.