First, and this sounds strange, but,,, vacuum the plant from top to bottom. This will get rid of a large number of the nymphs and adults. Make sure to remove all of the webbing.
Second (and I have and do use this), mix a half gallon 70% isopropyl alcohol with a half gallon water. Add 2 tsp potassium bicarbonate and around ¼-½tsp castile soap.
You can also still mix in spinosad, at this point, if you like. However most people will not continue using the spinosad through the rest of the flowering cycle.
Spray every other day for the first week, covering the plant top to bottom. Make sure you get it everywhere. Spray the walls, floor, ceiling, equipment, pots and everything else in the area. The second week spray every third day.
Keep monitoring the plants using magnification and check everywhere.
This mix can be sprayed all the way through flowering. The alcohol kills on contact and then quickly evaporates away, the soap (and spinosad) leave some residual effects, and the potassium bicarbonate will help prevent and or kill fungal infections.
The soap and potassium bicarbonate can be used in greater amounts during vegetative growth. You can also add silica for foliar applications with this.
Good luck friend!