Gravity concerns slow fermentation

I have returned to home brewing after a long leave of absence and would be very grateful for some advice just to make sure my wort is still going in the right direction as I am getting a bit concerned. I replaced the time expired yeast packets with new ones and have made two kits, a Brewmaker Strong Export Bitter and a John Thompsons Strong XXX Bitter. Everything was properly sterilised. It's now day 6 and the wort of the Brewmaker is 1.030 and the Thompson's is 1.020. I remember clearly when making these beer kits before that they would generally reach a gravity of about 1006 after 6 or 7 days and become ready for barrelling, it says this is the beer kits instructions.

The gravity readings are taking longer than usual to come down, the temperature of the wort is about 20°C and they both seem to be foaming away quite happily! Am I worrying unnecessarily about the slow fermenting speed could the replacement yeast work slower than the original time expired batches? Any advice would be very helpful and much appreciated.

Thanks. Jon.