Can anyone share any anomalies in the 'known' list of serials and Sights?

I know many people believe the 550K - 1 million range for Type 1 lockbars, but a gentleman has just shares pics of his Lend Lease 52#### and it has a Type 1 lockbar. Haven't seen rest of rifle, but thisnisnt the first time I've seen a serial outside of normal range.

I picked up a May 1942 SA with a May 1942 barrel. It had been through a rebuild and had every part warime, except the bullet Guide which was stamped with notch. It was a BA4 9-66 Rebuild.

Every part was correct for serial range:
SA 5 trigger group with 2 SA Hammer, 6 SA Safety, Plunger with Wings, milled trigger Guard.
Arched Lower Band
Single Slot Screw (basically brand new)
Front Sight Seal
Follower Arm without modification
Short Fork Follower Rod
Stock all Matching in Colour but no cartouches, but a single Proof stamp near Trugger Guard.
8 Follower
Ww2 buttplate.
Rounded Clip Latch
SA 3 Follower Rod with post war modification

The only incorrect parts were:
Flush Nut sight but with Knurled Knobs
Stamped rear handguard clip
The aforementioned Notch bullet Guide.

Do you guys think this was a corrected M1 or that it arrived like this?

It also has Tonsper on front left of barrel, however I don't believe that it is a British Lend Lease Rifle. Serial 617639.

I have since changed this into into all ww2 rifle correct to serial except for E McF Stock which is just a smudge too late, but like thefush nut question. There is always some overlap and rifles were not always built in order.