It is reported, TRON will launch virtual machine on May 25 (UTC+8), mainnet on May 31, token migration on June 21 and the first 27 super representative elections on June 26. With this date approaching, today, MERCATOX announced that it would support the TRON blockchain upgrade and token migration. Investors only need to deposit TRX’s ERC-20 tokens to MERCATOX before June 24th in 2018 (UTC+8) and will receive the equivalent TRX token after mainnet launch. No transaction is affected during the migration.
As a digital and crypto-currencies exchange, MERCATOX provides users with a multi-currency e-wallet with convenient service and instant transfers. The platform also provides excellent payment service with variety of payment methods and allows exchange of any virtual currency.

Here is what you should know about TRX migration: https://medium.com/tron-foundation/guide-to-independence-trx-token-migration-269302b6655c