I live close by there. The cycle path from Birchanger down towards the M11 bridge is paved, but then it turns into gravel/packed mud. You can cycle along it on 25mm tyres, but you'd want to take it easy.
There's roadworks on the roundabout before the M11 one, and on the road down to the M11 roundabout. This keeps traffic to a single lane. So the M11 roundabout is easier than usual, with fewer cars around when the lights turn green. However, you need to be confident in traffic as you need to hold the middle of the central lane (of 3) as you head eastwards around the top part of the roundabout. I've seen some airport workers ride their bikes on the footpath that goes around the roundabout.