That document linked above states that the product has been withdrawn from the market in March, that it no longer poses a threat after multiple refueling cycles and that 75 MAX are expected to be affected.
So to answer my own question partly, it's deemed a:
- non issue for previously treated but operated aircraft due to dilution (eg. 787, neo)
- non issue for COVID grounded aircraft due to product (non) availability
- issue for a certain type with 75 treated aircraft sitting on the ground for ages.