the [Grand Chamber of the] court found there had been no violation of the European convention on human rights because the men had attempted to enter Spanish territory in an “unauthorised” manner. [...]
The grand chamber’s ruling comes three years after the same court unanimously ruled Spain had violated rules that prohibit collective expulsion and had denied the right of effective remedy. The latest ruling followed an appeal by Spain.
The 2020 GC decision was also unanimous. As an aside:
the governments of France, Italy and Belgium ended up joining Spain’s appeal, indicating that the verdict could have a huge impact on the future of Europe’s migration policies.
I found another ("collective expulsions") case, Khlaifia and Others v. Italy in which was described as "partial reversal" of a the lower chamber's decision
How often do such [partial] reversals happen at ECtHR's GC, not restricted to immigration matters? I.e. are there any statistics on this?