It really depends on the plan. I know you are nearing the end of SSP2 so I will speak to the SSP3 plan. In that one, the intermediate plan has weekend rides around 3-4 hours long with a target TSS of ~150-225 where as the basic plans has weekend rides 1.5-3 hours long and ~100-200 TSS. The weekday rides in the intermediate plan will also have harder intervals (e.g. tempo bursts 2 x10 in the basic plan vs 3x15 in the intermediate). In general the TSS for the intermediate plan will be anywhere from 50-300 tss higher than the basic plans, again this is in reference to SSP3 but will be similar for other plans too.
If you wanted to do harder weekday rides (and are confident you could recover from them), you could get an intermediate plan and then lower your volume a bit on the weekends to match your time available to train. You could also add in an extra time in zone 2 to your weekday workouts to increase your TSS. This is always a good option, especially while you are building your aerobic base.