Richard's Response to the death of Edward IV
Assuming that Hasting's sent his messenger to Richard following the 1st Woodville Council (between 12th and 14th of April 1483) Richard would have received the news of his brother's death around the same as Anthony Woodville (16th April). His response, however was very different. Allowing himself, a little time to grieve, before he called his Secretary, John Kendall, to prepare two letters. The first was to the Queen Dowager, expressing his sorrow and condolences on the death of her husband, King Edward IV. The second was to the Council, assuring them that the loyalty he had always shown to his brother he would give to his brother;s son, Edward V. He also let them know that he would be travelling to London to take up his appointment as Lord Protector, according to his brother's wishes as dictated in his will.
Finally, in no uncertain terms he let them know he was aware of all the goings on and warned them that any illegal acts undertaken thus far would be met, not only with his displeasure, but with the full weight of the law. Richard of Gloucester was no pushover.
Calling his household together, he informed them of the death of his brother, and called for mourning attire to donned before a service of mourning was held and each and everyone was called to swear their oath of allegiance to Edward V.
Barely had the dust settled in the wake of the message from Hastings when a second messenger arrived from Henry Stafford, Duke of Buckingham, offering his support and 1000 men at his command. Richard responded with a message back. He was grateful for his support but the number of men should be limited to three hundred only. He was intending to rendevous with the King's party at Northampton and Buckingham would be welcome to join them.
Doubtless messengers went back and forth over the next few days until Richard was satisfied all was in place, before he departed for York with a retinue of three hundred men, all dressed in mourning. On 22nd April, or thereabouts, A Requiem Mass was held in the Minster for a beloved brother and King. Afterwards, Richard led the oath of allegiance given by the clergy, local gentry , the Mayor, Aldermen and prominent citizens of the city.
Richard left York to travel south on 23rd April.