Looking in the owners handbook for my 98 V70- blue text is mine
Oil Quality
Petrol engines:ACEA A2/A3 this would include the B5244S
Oil which meets ACEA A3 is recommended for turbocharged engines
...
Synthetic or semi-synthetic oils may be used if they fulfil the quality requirements as specified above
this implies the expectation of not using synth unless it meets spec
This chart is very similar to the chart in the handbook with the 10W/30 and 10W/40 shaded pink eg the Volvo recommendation
The only issue I can see with various weights of oil is the /30 is specified for ambient temps up to 30c and we get a few days each year when it goes above that