(Bloomberg) -- Japan’s benchmark yield briefly rose above the central bank’s ceiling for the first time since its January meeting as traders continued to bet on further policy tweaks.

The 10-year yield climbed to 0.505% before erasing its advance. Investors are readying to hear from Kazuo Ueda, the nominee for the Bank of Japan governorship, who is due to face confirmation hearings in parliament on Friday.

Ueda, an economist and a former BOJ board member, isn’t known as someone who’s either a strong dove or a hawk. But, speculators are betting that the BOJ’s cap on bond yields will eventually have to be scrapped regardless of who the next governor is as the policy tool looks increasingly unsustainable.

“What’s behind the mover higher in yields is speculation of a change to yield-curve control,” said Ayako Sera, a market strategist at Sumitomo Mitsui Trust Bank Ltd. “Should the BOJ change policy abruptly like it did in December, bonds would tumble, so there’s a sense of caution in the market.”

In December, the BOJ doubled its policy ceiling to 0.5% in a move to improve market functioning but just ended up buying more government bonds to defend the new cap. It pushed back against intensified speculation for more adjustments at the January gathering, keeping policy unchanged and doubling down on its defense of the yield-curve-control program.

Yields on two- and five-year notes outpaced the rise in the 10-year rate on Tuesday as they rose 1.5 basis points each. The 10-year yield rose as much as 0.5 basis point.

“Some investors may be concerned that Ueda may hint at a future removal of the negative-rate policy,” said Ataru Okumura, a rates strategist at SMBC Nikko Securities Inc. in Tokyo. “These investors may be preparing for any situation that they could face.”

--With assistance from Saburo Funabiki.

(Adds strategist comments in fourth and last paragraphs.)

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