It sounds like the issue with your iPhone 13 Pro's screen turning yellow might be related to the software update rather than a hardware defect. You can try to:
Check Night Shift and True Tone Settings in Settings > Display & Brightness.
Adjust Color Filters: Settings > Accessibility > Display & Text Size > Color Filters.
Reset All Settings: Settings > General > Reset > Reset All Settings. (This will reset your preferences and settings but will not delete your data)
Restore your iPhone or completely reset your iPhone (backup before use, as this will remove all the data from device)
If none of these steps resolve the issue, it might still be a hardware issue that coincidentally appeared after the update. In that case, it would be best to follow the advice of the iStore and get the screen checked or replaced if necessary.