Mine was 11. Had pain in my hip that meant I had to use a walking stick to get the quarter mile up a hill for work and I felt horrendous.
I took 10,000 IU three times a week for months and spent ten minutes out in the sun around 2pm every single day for the entire summer.
That got it up to 26 after a year.
It took a year (and another heatwave) before I didn't have the hip pain, the following year, I took one 10,000 IU a week and normal ones on the other days.
Now, I take normal dose D3 (as D2 isn't anywhere near as good and I'm not vegan) daily in a multivitamin and if I start hurting, I double up (as advised) on a separate high dose.
Obviously, to get osteomalacia, mine had been very, very low for a very, very long time, which is why it took so long, but the other symptoms probably started easing within 2 months.
Had my local health authority approved injections, I'm sure it would have resolved sooner.