Southend has bitten off a lot in terms of annual growth rate with Ryanair basing aircraft at SEN, and experiencing a bit of indigestion (eg security screening queues). Perhaps time to focus on ironing out all the kinks in standard daily operations.
Flights that are full in July/August with small children and people who fly just once a year will exert a greater strain than those in May. Other airlines may be watching to see how SEN performs in early August to verify operational robustness before any kind of new route announcement