Ever had a person you couldn't stand, but can't do without? Queen Margaret does. York is now the leading magnate in the country, with his supporters in key positions following Lutterworth. However, the situation is not so bad on examination. Most of the nobility dislike the ambitious
York as he has obtained his position through violence & he has therefore got few (if critical) supporters.
Into this fertile situation we now have Queen Margaret moving Centre stage to lead the Lancastrians. Her husband is useless, her son's succession threatened by the protector York (who is his primary rival claimant to the crown.) The Queen may have no time for all this parliamentary nonsense and ruling in any way other than by decree, but she still has many potential followers - not least from sons of the dead at Lutterworth who feel they have scores to settle.
Queen Margaret gets York stripped of the Protectorate in 1456 & begins stuffing posts with Lancastrian supporters. The Yorkists are driven out and his main allies, the Neville family, find their rivals the Percies are getting more favour. Margaret leaves the unsafe London to set up a new court at Kennilworth in her Midlands power-base, buys cannon & gets the Royal armouries stock up. Clearly, a reckoning with the upstart York is on the way.
She would finish him off once and for all but York & Warwick are both needed for the moment because of French raids on the South coast mean the French-born Margaret is unpopular and - even worse - Warwick is required to sort it out as the Captain of Calais. Everybody in the capital and the southeast seems to like these Yorkist types a bit too much!
So, how do you get rid of the popular but disliked Warwick? You starve him of funds for one, but then he just resorts to piracy to pay the bills. You call him back to face charges and get him locked up, but his supporters fight with yours and he refuses to come, claiming you're trying to murder him. As if.
Everybody relocates to their centres of support. The Queen is at the Midlands; York is in the Welsh Marches; Warwick is in Calais. Most popular support in the country goes to the Lancastrians, and at long last the fight must inevitably be resumed - drive out the presumptuous Yorkist Traitors!