Although Boris Johnson wasn't Douglas Ross's first choice for UK Conservative leader, he did support him in the 2019 contest against Theresa May.
Although he hasn't said if he regrets the decision, he certainly has changed his mind. He has done it more than once.
Boris Johnson was withdrawn by Ross in January. He claimed that his support had become untenable due to the lockdown parties, and called for a confidence vote.
He reversed his position when the war in Ukraine began, arguing that domestic political upheaval would be in the hands of Vladimir Putin.
This seems not to be a major concern as Mr Ross has now made a double U-turn and voted for the motion de no confidence in Boris Johnson’s leadership.
He stated that, while the timing of voting was not ideal, he had been listening to the public's anger over Partygate, and couldn't in "good faith," continue to support the PM.
This decision puts him in line with most of his Tory colleagues at Holyrood. However, his many changes in position raise questions about his leadership abilities.
One pro-Johnson MP stated that he wouldn't be willing to drive Douglas Ross anywhere because he doesn't know where the journey will end.
The truth is that the leader of the Scottish Tory Party would have been criticized and embarrassed for his flip-flopping style, regardless of which way he voted.
Either because he backed a law-breaking PM, which the Scottish party blames for the recent losses in the local elections, or - as it turns - because he left him despite insisting he should lead the UK through Ukraine.
Ross was among the 148 Tory MPs that expressed no confidence, and four of the six Tories who had Westminster seats in Scotland.
The Scottish rebels are quite unusual in that they all publicly disclosed how they voted in a secret ballot.
After casting his vote against the PM, John Lamont, the MP, quit as an aide for Liz Truss.
It is not known if David Mundell, the former Scottish Secretary who was dismissed from Cabinet by Johnson, will be allowed to continue his role as trade envoy to New Zealand following his rebellion.
Andrew Bowie, the fourth Scottish Tory MP who refused to support the PM, resigned from his position as vice-chair of UK Conservative party.
This is not sustainable. It is difficult to imagine, for instance, a UK general elections campaign in which key Scottish Tories are unable to endorse their candidate for Number 10.
The other side of this argument - still standing behind their leader - is MPs David Duguid, and Alister Jack who sits as Scottish secretary in Cabinet.
In a statement, Jack stated that the PM's 211 votes were a "clear majority". He said it was time for Partygate to end and "get on with what really matter".
This may just be wishful thinking, as Boris Johnson won the election and has publicly lost the confidence in two fifths of his MPs.
This is a worse result than the one he got from Theresa May, and she was forced out of office six months later.
Boris Johnson's fate is not certain, but it is possible that he will still be able to lead in the months ahead.
Rebellion can become a habit and the government could lose if just a few Tory MPs change sides in Commons votes. Ministers could be diverted by the threat of being disowned.
If the Conservative party is defeated in the forthcoming byelections at Tiverton, Honiton and Wakefield, there are further problems for them. This would be a serious setback for the Tories.
Another potential flashpoint is a privileges committee inquiry into whether Boris Johnson knowingly misled Parliament over Partygate.
This does not mean that the PM, who is protected from another confidence vote for one year, is without agency. In an effort to renew his appeal for Tory MPs as well as the wider public, he has the power of resetting policy.
In the days ahead, he is expected to introduce new measures to reduce childcare costs and to help more people get onto the housing ladder.
Some speculate that he might be able to concentrate if he raises the possibility of an early general elections.
His critics are currently without an obvious candidate to succeed him as Tory leader or PM.
Boris Johnson has won the confidence vote and his premiership will continue, but with less authority, which is difficult to regain, as other prime ministers have discovered.
