Hi Kanishk,
No, I haven’t been able to resolve this. In PyTorch GitHub it’s mentioned all models have been trained on 8x V100 GPUs with the following command
python -m torch.distributed.launch --nproc_per_node=8 --use_env train.py --lr 0.02 --dataset coco -b 4 --model fcn_resnet50 --aux-loss

I only have access to two GPUs. As a work around, I tried with nproc_per_node=2 and -b 16, but still couldn#t reproduce the reported accuracies.