BJP and TDP have worked together and came to power in the 2014 elections. After many critical situations, both parties have divided and contested individually in the 2019 elections.
After facing humiliating defeat in elections, Naidu openly stated breaking from the BJP is a mistake. He shouldn't have opposed BJP as it affected him a lot. Since then, he tries to get closer to BJP, finding every chance to settle the issue between them.
BJP is not positive towards Naidu, they know he dumps them if situations are not favorable. For this, they have avoided Naidu's company.
Now after witnessing the BJP-Jana Sena alliance, Naidu's plans of moving closer to BJP are spoiled. Naidu became weak after the defeat in elections. Most of the leaders left the party, and many leaders are looking towards BJP and YSRC. In this case, Naidu's only hope to save the party is getting possible support from the Central government to attack the Jagan government. Unfortunately, he failed in maintaining the coordination with the Central.
If the BJP-Janasena alliance works according to the plan, TDP will slowly faded from the political race. Their alliance becomes alternate for the AP people, neglecting TDP as the main opposition party. People treat the alliance as third front, and many can be attracted to it. The political equations completely changes, and it becomes a threat to TDP. Naidu is in great danger with the alliance of both the parties.