You're welcome.
The background, helps, being not all of a sudden. Really leaning towards a exhaust restriction, as it was on mine, it progressively got weaker.

Disconnecting the downpipe at the turbo will confirm this. I chose to straight pipe the Cat, but I have no emissions testing. If you have testing, I would recommend hollowing out or getting a generic unit. The OE units have been NLA for years now.

If found to be a exhaust restriction, it needs to be addressed. It will only get worse. The biggest detriment being the extra 300-450 degrees increase in EGTs stressing the head.

Best of luck