This is what I was thinking it had happened. it definetely felt that the bulb was brighter. I had more ilumination in the room than I remember from last session (about a month), so even though the coating has not changed or scratched. Can this happen in a short period of time. ?
Either way, I just bought some Kodak Model A with OC filters from ebay. I hope these are good enough for Ilford VC paper.