Can I go from OTM to UTM reconstruction?

I am 6 weeks post op from a breast reconstruction With OTM implants and am regretting my choice. I feel like the implants (420cc) are weighing heavy and I am anxious about them dropping with no support. I have had a previous lift about 4 years before getting cancer. It was me who wanted the OTM thinking that under would impact on my exercise, but I now see that this was ill informed as man people do just fine with dual plane or under the muscle. Would UTM provide better support?