OK so here goes. Firstly the OP coin is definitely not a large flan obverse die, and without even looking for a die match I think we can clearly see that from the first of the below images, in which I also encircle the rose, which is definitely the large Rose 4 - the third coin in the row is also a regular flan, but with rose a 5 for comparison.
The second row of three coins are regular flan 3ds which have the large rose 4 - I think the proportion of the OP bust, relative to the inner circle, and relative to the rose, indisputably show that it is the same type as the second row of images, namely a regular flan die with large rose 4.
The third row of coins are large flan 3ds with rose 5 - from those 3 images we can get a good idea of scale to compare with OP coin.
So I 100% stand by my mule classification BA-3B:a namely it's a large flan reverse paired up with a regular flan obverse. BCW lists one muled pairing of this type, but not this particular obverse legend, making it unrecorded by them, and rare regardless.
The punctuation wasn't included in my classification because BCW don't use it, saying themselves that it has no significance, other than I guess in identifying die matches and maybe for further micro-organising the series?
Phew! Glass of wine and shower - you might recognise one of the large flan coins, Dave? Have a good Easter.