Cyclone not finishing when using BPPARAM=MulticoreParam(workers = n))

[Hrovatin]

I had used cyclone before with BPPARAM=MulticoreParam(workers = n)). This has worked well up to now. But now when I have tried to run it again the function call never finished, even with a minute number of cells. No errors are reported - the jupyter cells just keeps showing running status. I call cyclone with rpy2 from python. My collaborators who recently made a fresh conda env also reported the issue on a different server; we tried multiple datasets. However, if I remove the BPPARAM parameter from cyclone call it runs through.
I assume I have updated my R packages in between, which may have caused the issue, as then scripts worked well in the past (last summer) with BPPARAM.

> sessionInfo()
R version 4.0.2 (2020-06-22)
Platform: x86_64-conda_cos6-linux-gnu (64-bit)
Running under: Fedora 28 (Twenty Eight)

Matrix products: default
BLAS/LAPACK: /home/icb/karin.hrovatin/miniconda3/envs/rpy2_3/lib/libopenblasp-r0.3.10.so

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
 [3] LC_TIME=en_GB.UTF-8        LC_COLLATE=en_GB.UTF-8    
 [5] LC_MONETARY=en_GB.UTF-8    LC_MESSAGES=en_GB.UTF-8   
 [7] LC_PAPER=en_GB.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=en_GB.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] parallel  stats4    stats     graphics  grDevices utils     datasets 
[8] methods   base     

other attached packages:
 [1] scran_1.18.7                SingleCellExperiment_1.12.0
 [3] SummarizedExperiment_1.20.0 Biobase_2.50.0             
 [5] GenomicRanges_1.42.0        GenomeInfoDb_1.26.7        
 [7] IRanges_2.24.1              S4Vectors_0.28.1           
 [9] BiocGenerics_0.36.1         MatrixGenerics_1.2.1       
[11] matrixStats_0.61.0         

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.7                compiler_4.0.2           
 [3] bluster_1.0.0             XVector_0.30.0           
 [5] bitops_1.0-7              BiocNeighbors_1.8.2      
 [7] tools_4.0.2               DelayedMatrixStats_1.12.3
 [9] zlibbioc_1.36.0           statmod_1.4.36           
[11] lattice_0.20-45           pkgconfig_2.0.3          
[13] Matrix_1.3-4              igraph_1.2.6             
[15] DelayedArray_0.16.3       GenomeInfoDbData_1.2.4   
[17] locfit_1.5-9.4            grid_4.0.2               
[19] scuttle_1.0.4             BiocParallel_1.22.0      
[21] limma_3.46.0              irlba_2.3.3              
[23] BiocSingular_1.6.0        magrittr_2.0.1           
[25] edgeR_3.32.1              sparseMatrixStats_1.2.1  
[27] beachmat_2.6.4            rsvd_1.0.5               
[29] dqrng_0.3.0               RCurl_1.98-1.2