The idea behind UBI is one that I don't have an issue with however its been proven many times not to work because there are factors that limit success outside of just giving people money. One of the biggest issues is the more money you have circulating in the public the more cost of goods will go up. Eventually you'll reach a point where it doesn't matter how much cash is being handed out because the cost of goods have gone up so much no one is any further ahead.
I've seen this play out in areas where minimum wage was suddenly massively increased. In Canada a number of the provinces decided to massively incease minimum wage over a relatively short period of time. The end result seems to be much higher cost of goods - food and energy costs in particular have sky rocketed - but so have rents, house costs, etc, etc. It doesn't take much maths to work out those people who were earning the minimum wage really are no better off. Whats worse is that those who were on a higher wage but didn't get any bump up now also have to pay more for everything so are effectively worse off. I have friends and family there who were living comfortably in 2008 but struggle these days.
So yes while I love the the idea of things like UBI I really wish people would realise there are complications beyond just the happy, smiley good intentions.
EDIT: And to actually answer the original question that was posed... no I don't think there will be a rush into PM's because unlike a one off payment a regular payment and that regular extra boost of cash being fed into the economy will cause inflation which is likely where most of the money will go.