The 1p and 10p counter sheets, and 2nd class business sheet with M19L code have been reported.
Both counter sheets were printed on 19/02/2019.
This suggests that there were several stamps printed in mid-February so we should look out for the other make-up values. The 10p and 2nd class have been found in Yorkshire.
Update 27 May: Andy P's comment -
"Last week (22/5/19) I received an order of various definitives from the Philatelic Bureau and the 1st SF/Large they supplied was M19L." Which is interesting as we dealers haven't heard about that one!
Update 2 June: Although I don't doubt that Andy has reported what he has seen, as we have not any any other evidence of this, nor photographic confirmation from Andy, I've scratched it for the time being. Others who have ordered reported receiving M17L from Tallents House, and I got M18L.
On the other hand Richard P has sent copies of the 100g Special Delivery with M19L printed on 26 March. (Pictures below the listing.)
In future I will only put details of new stamps on the blog if I have been sent a picture or a link to an online listing which shows a picture. All eBay sightings must be reported with an item number.
Full list of M19L stamps so far:
Counter Sheets
2911.9 2nd class - 25/02/19
2914a.9 1st class - 25/02/19
2913.9 2nd Large - 25/02/19
2916a.9 1st Large - 25/02/19
2985.9 100g Special Delivery - 26/03/19
3001.9 - 1p deep crimson, 19/02/19
3010.9 - 10p dull orange, 19/02/19- reported on both SBP2i and SBP2u
3020.9 - 20p green reprint, first on 19/02/19
3135 - £1.35 orchid mauve
3155.9 - £1.55 tuquoise-blue, reprint 14/02/9
3160 - £1.60 amber yellow
3230 - £2.30 gooseberry green
3280 - £2.80 spruce green
3345 - £3.45 dark pine green
3360 - £3.60 bright orange
Booklets
2936aC.9 - 1st class MCIL from mixed booklets, Marvel Comics 14.3.1, Birds of Prey 4.4.19 with a further one due for D-Day on 5.6.19
Prestige Stamp Books
4002P.9 - 2p green from Queen Victoria Bicentenary book
4050P.9 - 50p dark slate from Queen Victoria Bicentenary book - although this is a new shade I have not given it an 'a' number, although I expect when it is listed by SG it will not have the same base number as in previous PSBs.
Business Sheets
2911B.9 - 2nd class blue, printed 05/02/19 on SBP2u
2913B.9 - 2nd Large blue, printed 06/02/19, reported to be on both SBP2u and SBP2i but not necessarily with that date.
UPDATE: Images of both 2nd class and 2nd class large business sheets.
100g Special Delivery
There will be no more comments or additions to this post,
any new sightings/reports will be on a new post.