'Should' be okay, it's been known before to get a build up of sludge with oil that's a bit past its time causing the light to either come on or flicker, but you're doing things right, it was just a thought that was all.
Always best to change oil when it's warm to help avoid this scenario though.
I must admit to having a bit of a laugh with you, and copied the spec verbatim out of the handbook. I thought you were going to say about using bike specific or even fully syn in the Fazer. We all know oil debates can run to several pages on forums.
I used to use Comma car oil semi syn 10W40 in all my bikes. exceeds the spec given in the handbook.
I also used to do work on other peoples bikes, who (being unenlightened or loaded) wanted JASO MA2 oil, I don't have time to do extra work now, with family and work commitments, so having a couple of barrels left over from that, it's what I use in the Fazer. When it's gone, it'll be back to Comma.
My ZRX1100 is tuned to the bollox and has run all it's life on Comma car oil. Puts out over 160 BHP at the rear wheel.