P0022, Risk of Timing Issues on 1GR-FE

My truck just rolled over 253k miles yesterday. It has been very reliable, no drivetrain issues whatsoever.
I purchased the truck used at 212k miles. One owner, well taken care of. Soon after it threw timing codes on both banks. After reviewing the inspection sheet, it was clear that the dealer put cheap, bulk oil in. I purchased Toyota OCV for both sides, but never installed them because after the first oil change the codes went away. No timing codes (until the last 6k miles) after that.
My typical oil change interval has been 10k miles on Amsoil. Prior to my last oil change the truck started throwing the P0022 code again. Only that code, only Bank A. Since I was doing the transmission and transfer case anyways and was heading on some long trips, I decided to do the engine oil too although it was only at 7,500 miles. It looked much darker than usual, but no metal flakes. Thought there was potential for that to affect the OCVs. Afterwards it took almost another 1k miles to throw the P0022 code again. Since then, it will go about 500 miles between codes if I reset it. I'm now 5k miles into that oil change.
The only indicator that anything is wrong is the code itself. The truck is running 100% normally as far as I can tell.
Any insight on the odds that I have a more serious timing problem than just an OCV? From the research I've done on here, a chain that is stretched too far for the tensioner to compensate for is the most likely major issue. Is this something that commonly kills these engines? It seems like there aren't many of them around with 250k + miles unlike the 5vz, so that isn't very comforting.
My plan for now is to swap the OCV on that side. Maybe open up the inspection window and check the tensioner too.
FWIW, I'm itching to go back to a 1st gen anyways. Despite loving the ease of putting bigger tires on these, the interior, and more power I'm over the bigger truck and more complicated electronics and engine. That's probably contributing to wanting to be done with this one.

 

The most common cause of timing codes is typically the OCV or a stretched/jumped chain, if oil changes were neglected the screens can also get plugged which will cause timing codes.

As far as the timing chain killing the engine I've only ever heard of 1 or 2 that actually broke one, they typically start making noises and throwing timing codes long before they let go. Toyota tends to have a more robust timing chain setup than some other manufacturers (Gm/Ford) but they still eventually wear out/stretch, at 250k it certainly wouldn't be surprising if it ends up needing new timing components.

If you already have the OCVs might as well throw them in and cross your fingers before you dig into the timing system.

 

Like Dm93 said, if you already got new OCVs on hand Id put them in and see what happens. Could be worth checking the oil screen too, but if its had regular oil changes as you imply, I doubt you'll find anything there.

You can skim through my thread here if you want some pics
https://www.tacomaworld.com/threads/1gr-fe-bank-1-vvti-issues-p0011-p0012-p0016.770671/

 

Update, I was wrong on the original post. It's bank 2 (Driver side?) not Bank 1/A.
Reset yesterday, I'm watching to see how many miles before it turns up again.