Most mainland Brits (54%) now don't care whether Northern Ireland stays in the UK or not - an increase from 41% in October. Only 24% said they'd be upset by the break up of the Union. https://yougov.co.uk/topics/politics/articles-reports/2020/04/22/brits-increasingly-dont-care-whether-northern-irel?utm_source=twitter&utm_medium=website_article&utm_campaign=sam_northern_ireland

Mainland Brits do nevertheless tend to want Northern Ireland to remain part of the UK, by 37% to 27%. But another 36% aren't sure. https://yougov.co.uk/topics/politics/articles-reports/2020/04/22/brits-increasingly-dont-care-whether-northern-irel?utm_source=twitter&utm_medium=website_article&utm_campaign=sam_northern_ireland

At the same time, there is more support than not for a border poll in Northern Ireland, by 36% to 25%
https://yougov.co.uk/topics/politics/articles-reports/2020/04/22/brits-increasingly-dont-care-whether-northern-irel?utm_source=twitter&utm_medium=website_article&utm_campaign=sam_northern_ireland