If the current taper schedule is working well for you - especially as you're already at 10mg and things seem to be looking good, I wouldn't be too concerned. If all's going well, then you'd rather get off steroids sooner than later.
However, if you feel like you might be close to flaring up then you could speak to your GI specialist about tapering at a slower rate below 10mg i.e. tapering by 2.5mg per week instead - that only extends the taper by another 2 weeks or so.
Rio, 31 yr old male - diagnosed with UC in 07/2006.
Alternative therapies for several months (SCD, ayurvedic treatment, VSL#3): didn't work and became anaemic. Canasa, 2 daily: remission for a month then flared-up.
07/07-11/07: 4800mg Asacol (6 x 400mg, twice a day) & Aloe Elite.
Completed first (6 week) tapered course of Pred in 10/07, flaring up since coming off it.
11/07: Switched from Asacol to 12 x 750mg Colazal (3 weeks on it and symptoms got worse)
12/07: Asacol 4800 mg, Started Azathioprene 175mg, Prednisone taper from 60mg - Now on alternate days of 20mg and 10mg; 2/08: added 1 Pentasa x 1mg.