The business, which has its head office in Tividale, believes there could be lower volumes of passengers for the next 18 months as it admitted the long term effects of Covid-19 are "unknown".
It comes as the group swung to a pre-tax loss of about £4.8 million last year compared with a £2.6 million profit in 2019, driven down by the wider impact of the coronavirus pandemic.
For the year ended November 30 2020, group revenues were £78.1 million compared with £68.5 million in 2019.
Although bus services continued to run throughout lockdowns, albeit at reduced levels, they were recognised as essential public services and received Government funding support quickly.
Rotala said passenger volumes are gradually increasing as Covid-19 restrictions continue to ease.
Chairman John Gunn said: "The board has assumed that passenger volumes will continue to be negatively affected throughout 2022 and that true recovery will not occur until 2023. At this stage these are little more than best guesses because the long term effects of Covid-19 on travel, living and working patterns are fundamentally unknown.
"However, on the more optimistic side of the ledger, the Government's new National Bus Strategy does promise large scale fresh investment in bus transport. This must be a good thing for the industry in general.
"I continue to believe very firmly that the 'new normal' in the bus industry, whatever its shape, will more than ever require management which is swift to think and swift to act. The slow, indecisive and cumbersome will be left behind. I am glad to say that Rotala possesses just the management team to prosper in those conditions with exactly the right characteristics and attitudes that are going to be required.
"Thus I think that your company is very well placed to take full advantage of the opportunities which are likely to occur for both organic growth and acquisitions, and I am therefore confident about the prospects of the group in the years ahead."